What is the standard prescription for Valtrex (valacyclovir)?

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Last updated: April 25, 2025View editorial policy

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From the Guidelines

The standard prescription for Valtrex (valacyclovir) is 1 g orally twice a day for 7-10 days, as recommended by the 1998 guidelines for treatment of sexually transmitted diseases 1. This dosage is commonly used for the treatment of genital herpes outbreaks.

  • For initial episodes, the typical dose is 1 gram twice daily for 10 days.
  • For recurrent episodes, the dose is 500 mg twice daily for 3 days.
  • For suppression therapy to prevent outbreaks, 1 gram once daily is commonly prescribed.
  • For herpes zoster (shingles), the standard dose is 1 gram three times daily for 7 days.
  • For cold sores, a single-day treatment of 2 grams taken twice, 12 hours apart, is often used. It's worth noting that another study from 1998 also recommends valacyclovir 1,000 mg orally once a day as an alternative option 1. However, the most commonly cited and recommended dose is 1 g orally twice a day for 7-10 days, as per the guidelines 1. Dosage adjustments are necessary for patients with kidney impairment. Valtrex works by converting to acyclovir in the body, which inhibits viral DNA replication. It's most effective when started within 72 hours of symptom onset for outbreaks. Common side effects include headache, nausea, and abdominal pain. Patients should maintain adequate hydration while taking this medication and complete the full course as prescribed, even if symptoms improve before completion.

From the FDA Drug Label

2 DOSAGE AND ADMINISTRATION

VALTREX may be given without regard to meals. 2. 1 Adult Dosing Recommendations Cold Sores (Herpes Labialis) The recommended dosage of VALTREX for treatment of cold sores is 2 grams twice daily for 1 day taken 12 hours apart. Therapy should be initiated at the earliest symptom of a cold sore (e.g., tingling, itching, or burning). Genital Herpes Initial Episode: The recommended dosage of VALTREX for treatment of initial genital herpes is 1 gram twice daily for 10 days. Therapy was most effective when administered within 48 hours of the onset of signs and symptoms. Recurrent Episodes: The recommended dosage of VALTREX for treatment of recurrent genital herpes is 500 mg twice daily for 3 days Initiate treatment at the first sign or symptom of an episode. Suppressive Therapy: The recommended dosage of VALTREX for chronic suppressive therapy of recurrent genital herpes is 1 gram once daily in patients with normal immune function. In patients with a history of 9 or fewer recurrences per year, an alternative dose is 500 mg once daily In HIV‑1−infected patients with a CD4+ cell count greater than or equal to 100 cells/mm 3, the recommended dosage of VALTREX for chronic suppressive therapy of recurrent genital herpes is 500 mg twice daily Reduction of Transmission: The recommended dosage of VALTREX for reduction of transmission of genital herpes in patients with a history of 9 or fewer recurrences per year is 500 mg once daily for the source partner. Herpes Zoster The recommended dosage of VALTREX for treatment of herpes zoster is 1 gram 3 times daily for 7 days Therapy should be initiated at the earliest sign or symptom of herpes zoster and is most effective when started within 48 hours of the onset of rash.

The standard prescription for Valtrex varies depending on the condition being treated:

  • Cold Sores (Herpes Labialis): 2 grams twice daily for 1 day
  • Genital Herpes:
    • Initial Episode: 1 gram twice daily for 10 days
    • Recurrent Episodes: 500 mg twice daily for 3 days
    • Suppressive Therapy: 1 gram once daily (or 500 mg once daily for patients with 9 or fewer recurrences per year)
  • Herpes Zoster: 1 gram 3 times daily for 7 days 2

From the Research

Standard Prescription for Valtrex

The standard prescription for Valtrex (valacyclovir) varies depending on the condition being treated.

  • For the treatment of genital herpes, Valtrex can be prescribed as a 3-day regimen of 500 mg twice daily 3 or as a once-daily dose for suppressive therapy 4, 5.
  • For the treatment of herpes labialis, Valtrex is the only oral antiviral agent approved for therapy 5.
  • For the treatment of herpes zoster, Valtrex is more effective than acyclovir and equally effective as famciclovir at hastening the healing of zoster-associated pain and postherpetic neuralgia 4, 5.

Dosage Regimens

Different dosage regimens have been studied for the treatment of genital herpes, including:

  • A 5-day regimen of 500 mg twice daily 3
  • A 3-day regimen of 500 mg twice daily, which has been shown to be equivalent to a 5-day course with regard to key markers of efficacy 3
  • Once-daily dosing for suppressive therapy, which is the only antiviral drug approved for this regimen 4, 5

Treatment Approaches

The treatment of herpes simplex infections can be approached in different ways, including:

  • Intermittent episodic therapy
  • Intermittent suppressive therapy
  • Chronic suppressive therapy The choice of approach depends on defined clinical characteristics and patient preference, and an evidence-based dosing regimen must be selected 6

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Valacyclovir for episodic treatment of genital herpes: a shorter 3-day treatment course compared with 5-day treatment.

Clinical infectious diseases : an official publication of the Infectious Diseases Society of America, 2002

Research

Valacyclovir for the treatment of genital herpes.

Expert review of anti-infective therapy, 2006

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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